Construction of ordnance.



PATENTED JULY 28, 1903 "J, SGHINNBLLER. GQNSTRUGTION 0F ORDNANGE.

APPLIUATION FILED NOV. 16, 1900.

No MODEL.

Witnesses;

zo are thick in proportion to its bore.

ders havingr thick walls, especially ordnance,v

' Naveseet.

Patented uly 28, 1908. y

PATENT OFFICE,

JACOB SCH'INNELLER, or P1TTsBRe,.PENNsYLvAN1A,

coNsTRuol-IN oF ORDNANCE.

SPECIFICATION forming part of LettersPate'nt N 0, 734,965, dated July 28,1903. V

Application filed Novemlner'l 6, 1900. Serial No. 36,701. (No model.) l

gheny and State OtPennSylVania, have inact description thereof. My invention relates especially to the conclare the-following .to be a full, clear, and ex- .lo' struction of ordnance, although it is also' adapted for cylinders which are subjected to great internal pressure, such as hydraulic,

gas, and similar cylinders.l`

It is well known that when cylinders are subjected to a central force or' internal pressure the tangential stress'upon its inside and outside circumfereuces due to such force or pressure will not be anywhere near the same, and especially so if the walls of the cylinder Cylinare usually. made of steel, which is more or less elastic, or, more strictly speaking, has the property or ability of elongatiug under stress `a5 to an appreciablevdegree, so that when the pressure comes on the walls of the cylinder they will expand. Barlow,'ef Englandhas shown that the stress produced on any material comprising the walls of a cylinder by the 3o action of a central forceorinternal pressure,

, such as the explosion of powder in a gun or Huid-pressure in cylinders, diminishes as the square of the distance from the center in.- creases. His demonstration is based upon the hypothesis that the Varea of the crosssecl 4o walls of the cylinder to be divided into thin concentric rings, it is easy to see that the circumference of the outside ring will be longer than the inside one, Thus if the vthickness of the walls is equal to one-half the diameter ofythe bore the outside ringwill have twice the length ofV the insideone, and conse- L quently if the metal composing said rings has the same tensile strengthin all andif longitudinal stress, reduction of cross-area,

Scand temperature are disregarded for each .pound internal pressure per square inchI the 'inside ring will elongate circumferentially vented anew and useful Improvement in Construction of Ordnance; and I do hereby de.

about four ,times asniuch per unit of length 'as the outside one. vIn other words, the outside ring y being twice the length of the inside ring has 'ap capability of elongation' under a given strain per square inch of section of twice the `elongation of the.inside ring,`but' square of the distance from the center, it follows that it will be elongated per unit of length'only one-fourth as vmuch as'the inner ring. Asa consequence of the several rings theoutside one'will ofller the'least resistance to the internal pressurein the inside ring,

andthe nearer the bore we getV the greater the stressper square inch of section, the inside ring being subject to thegreatest stress per square inch of section.

most and that the breaking down ofthe gun or cylinder' will commence onthe inside.A In the construction of ordnance it has been attempted to meet this diculty by so conbrace, and in order to put them in place theyv are heated until their diameter becomes large enough to slip over the tube or cylinder.

7o It follows, there-A fore, that the inside ring will be strained the- After being slipped upon the tilbe or cylinder they are allowed to shrink thereupon, and this -shrinkage is such that it slightly dirninishes the bre of the tube to such an extent that a final finishing reaming of the bpre is necessary in order to 4bringsgit to the proper,

caliber. This indicatesthat a tremendous strain is egrerted'by the hoops upon thetube, so that-the tube is in compressionwhile the jackets and 'hoops are in tension. YConse-` quently when t-he gun is discharged t 'einitial compression of the tube must be,equal ized before tension can take place in it constuction I believe to be based upon a faulty principle. Steel or other metal has elasticity within certain limits, beyond which This jacket until' 'the stress of the exploding construction; and Fig.

it 'cannot' be elongated without receiving a permanent strain or set, and if the elongation is continued beyondthis'the limit of. the tensile strength of the metal ma),v7 he reached and the same become ruptured. Iiiordnance as at present constructed theinnei" tube, and possibly the inner jacket or jackets also, is under an initial compression, as above stated., Consequently the stress ofthe exploding pow? der is not resisted by theinner tube or inner its compression is neutralized; but the, stress is immediately transferred to and resisted by theV jacket-and hoops, and the stress on each layeris less and less as the numb'erand thickness of theda fers com posingv theivalis vot' the gun are increased. The jacket: and' hoops or .some of them, however, are under an. enormous initial vtensile stress ^by`reason,ofhaving been shrunk on the tube and on'each other, as above sta-ted. "Consequently the-amount o t' additional stress which they'can' bear before `reaching their elastic limitis very iniich reduced. y* In orderl ore- "Tore, for the jacket and hoops to wit stand` powder', as tell @is "iai-Stress tofwhih theral'@ l d,` afndfstill b e `Wthih their safety: limit,i t vnecessarythat they bje ConstrY ed ot' aconfderable thickness of metal, a much greater tl' cknes:` in would be required lijf' the stre f'tbeezpoding powder-.alos

Itis the object 'of injfinvelitizyn to i. .rcome the objet-:tions above noted; and totni.; end'it consists in consti-uciingjsuch gunsvr orji cylinders of a series of rings or iayersxwhich are secured one over the other by shrinking or forci the outer ones on the inner or. t, but onlJ .o such a degree thatthejackct y hoops are subject to only sufficient tension to holdthem securely in place andere not subject to such tension as will materially af` feet their power of resisting internal-stress and in making'said rings or layers of metal such tha-t'the property or ability of elongation of the metal lcompcnsing said rings or layers decreases fromtheinteriorof the cylinder to the outside thereof or from the innerv tubev tothe outer one or making said rings or layers of metal having the Same property or ability of elongation, but the tensile strength whereofincreasesin each ring from the in-V side oneout.

the enorme us in jacket (i will,

tionwith ordnance.

` ln'the accompanying drawings, Figure ll isI a longitudinal section through a modern coast-.defense gun, showingv the method of 2 is a similar View of a Wire-Wound gun. f A The coast-defense'gun (illustrated in Figi) comprises the inner tube 3, yin which is formed the bore and the powder-chamber 5. Surrounding. this tubetis the jacket 6, which extends about one-halt' of the length ot the tube ai the breech end thereof. Also surrounding the tube 3 in front of the jacket is the chase-hoop 7, and surrounding the for yvard or muzzle end of the tube is the hoop S. Outside of the jacket 6 are the two hoops 9 and 10,-and outside of these are the hoops ll and l2 and the trunnion-band 13. he gun will of course he provided with the ordinary breech-blockL-Y; but this forms no part of my invention.

The Wire-wound gun (illustrated in Fig. 2) is provided with a core-tube l5, in which is formed the bore and powdcr-chamber, as above described. This core-tube is Wound with a series of layers 16, of wire, three such layers being shown in the drawings; but obviously the number thereof may vary, as desircd. ends by suitable meansas, for instance, by the nut 17--andoutside of these layers. the gun is provided with the trunnion-jacket 18. At the breech it is provided with the bushingr 19 and facer-plate 20, which areprovvided with. the opening nook.

The various layersof the gun shown in Fig. .i are made of suitable steel having the property or ability of elongation in varying degrecs,v -Forinstance the core-tube 3 may.

have a certain degree of .ability given stress per nare inclu of v.surface it will elongate av certain amount per unit 'of length. The possess the property yor ability. in dog'rccnthat is, funot elongation i der the same stress per square inch ofy surface it will elongate a less amount per unit, of length than the core-tube in the-same manner the hpops and 10 possess the propertyorability of elongation., in a still lesser,

105 and will have a still less ability of elong ,tion than the hoops degree than the jacket, whilevithe hoops ll i) and l0.

and the various hoops will be over the oore-tu that they will be heldy firmly in place, but with only sufiicient initial ytension to hold them in place. The result is a built-up gun the various layers of which are fitted iirmly upon each other, but not `so tirmly that the outer layers will be vunder any great amount The jacket 6 fitted snugly These layers nare lconhned at their' for receiving the breech-r be 3 and over each other, soY

of tension or the inner layers under great v compression and in which the property or ability of elongation per unit of length vof the metal in the various la 'ers decreases from the core-tube outward to the outside of Athe gun in such a manner as to give practically a uniform ability to withstand internalstress by all the layers 'or rings. inasmuch as neither the jackets nor hoops are under any appreciable amount of tension, they are cach capable of receiving aneqiia'l amount of stress, and the stress which they are capable of withstanding is nearly equal to their limit oflelasticity, whereasin the in ner hoop or jacket could receive a stress only equal to its limit of elasticity minus the enormous initial stress under which it was placed, and the other hoops could. receive less and less stress from the inside one out. It

the old form lof gun` --will be readily observed that the jacket and hoops in my'gun can he made much thinner than in the old form'of gun, or, if made of the samel thickness, the gun Will be capable of withstanding a much higher pressure than guns made according to the old method.I As

above stated, the property or ability of elon gatio'n of the'various layers decreases toward the outside, and this decrease should be varied approximately as the square of the distance i of the various layers from the center, so that all said layers will bear approximately a uniform stres'sper square inch of section when the gun or cylinder is subjected to internal pressure.- The same principle is followed in the wire-wound gun shown in Fig. 2, in which the tube 15 possesses the property or ability'of.

elongation to a certain degree, and each-of the layers'of'wire 21 22 23 possesses this property or ability of elongation to a lesser degree than the core-tube 15 and each layer to a lesser` dei grec than the preceding inner layer.- The erty or ability of elongation in a lesser degree than the outer layer of wire. The various layers of .wire will be laid. upon each other snugly and with only sufficient tension to hold them firmly in place.

The various layers comprising the gun may be made of metal having the same property 3 or ability of elongation; but in that case the tensile strength of the metal would have to increase from the inside tube outward. The same effect will beobtained as in the other t construction, for, although the various layers when subjected to the full stress they are capable of resisting would elongate an equal amount p" er unit of length, still when said layers are allsubjected to a given or equal stress, asis the case in actual use, the ones composed of metal of higher tensile strength .will elongate av lesser amount per unit of length than those having a lesser tensile strength. oCqnsequentlyjhe former under a given stress have a less property or ability-of elongation tlian the latter under th`e .ame' stress.

'It will be understood that it is not necessary to apply theA foregoing principle to all the layers composing the Walls of the gun .or

pylinder, and especially'if such Walls are l composed of a large number of layers. VIt may be sufficient if twoor more of the layers,

. tubes, or jackets are constructed on this principle, and the -two o r more layers, tubes,`or jackets need not `necessari-ly lie' one over the other, but may be separated by one or more. layers, tubes, or jackets in which the degree .of elongation has been ignored. In gun con-- struction especiallv it 'may be desirable to veneers form the core-tube of metal best suited to withstand the friction ot' the shell andl irrespective of its ability to elongate. Se, too,

the outside or trunnion bands should preferf ders, or the like-and these cylinders may be either built. up of tubes or layers one over, the other or of an internal tube wound with 1 one or more layers of wire. VIneither case the cylinder will be so constructed that the stress 'will he divided among all the layers, so that each layer will bear substantially the saine stre'ss per square `inch 'of section. Further more, the layers will be subject to only a very slight initial tension, so that the cylinder may be subjected to an internal pressure much greater than in the present make of built-up cylinders..y

What I-.claim as my invention, and desire to secure by Letters .latent, is-

1. Acylinder ofthe character specified hat ing walls composed of metal, theproperty or ability of elongation under a given stress of the vmetal inLits normal condition in different concentric p rtions of the walls of said cylinder being diiierent and decreasing from the inside outwardly.

.2. A.cylinder ot the character speciied. Vcomposed of a series of layers or rings,ltwo or more of said layers or riugsbeing made of metal having diiferent degrees of the property ori ability to elongate under a given stress, said property or ability ofelongation beinggreatest in the innermost one of said layers or rings and decreasing outwardly.

3. A cylinder of the character specified composed of a series of layers or rings, said layers or rings being made of metal having different' degrees of the property or ability to elongate under agiven stress, said ability or property of elongation being greatest in the innermost on'e of said layers or rings and decreasing outwardly.

4. A cylinder of the character specified composed of a series of la, ers or rings, two or more `of said layers or rings being made of metal' having different degrees eof the prop erty or ability to elongate under a given' stress, said ability or property to elongate being `eatest insaid layer or'ring nearest the bore Aand decreasing from said inner layer or ring to the `outer one thereof...

5."V A cylinder of the character specified hav- IIO lI2C) ing walls composed of metal,the property or ,ability f elongation under given stress of the metal in its normalcondition in different concentric portions of the walls of said cylinder being d'iEe'ret and decreasing from the inside outwardly approximately asthe square of the distance from the centerf4 t 6'. A cylinder ofi-the ycharacter specified Vgivenfst-,rees ofghe nietelof two or. more of said layers or rings' being difexentin said layers or rings and decreasing from said innexlayer or ring to the onbelone thereof, te' under a given-stress, said property saidI rings oz' layers being under an initial ity ofelongbion being greatest in the l tension just; sufficient to hold them inl place. :osi: one ofsaid layers or ringe and deing outwardly?. approximately. as the SCHINNELLER, have hereunto set my hand..

oouiposel' -of a series of .layers or rings, said is er'rjpgs being made of metal having meut degreesof the property or ability to meer@ of the disbanoe' from the center. -i T 1 7, A cylinder of the character epecied 'JACOB SCHINh-ELLER' compose@ of a series of layers or' rings, the pi'operiy orl ability of' elongation under a,

Witnesses:

ROBERT Ci TOTTEN, F. W.,WINTER. 

